Measuring Functioning in People with Fibromyalgia (FM) Based on the International Classification of Functioning, Disability and Health (ICF)—A Psychometric Analysis
- 29 July 2011
- journal article
- research article
- Published by Wiley in Pain Practice
- Vol. 12 (4), 255-265
- https://doi.org/10.1111/j.1533-2500.2011.00488.x
Abstract
Instruments to assess functioning in patients with FM vary considerably in their content and are often symptom-specific. This study aimed to examine whether it is feasible to construct a psychometric-sound clinical instrument to measure functioning in FM based on the Brief ICF-Core-Set for chronic widespread pain (CWP). Two hundred and fifty six people with FM completed the Brief ICF-Core-Set. The Rasch model was used for analysis. Once ordering of response options of ICF categories was ensured, the following properties were studied: fit of the ICF categories to the Rasch model, the targeting between ICF categories and a person's abilities, unidimensionality, and reliability. Six ICF categories were rescored due to disordered thresholds. Five ICF categories were removed due to high model-misfit and differential item functioning (DIF) for gender. Scores from 46 participants were excluded due to extreme scores. The ICF categories included display consistency with an underlying unidimensional construct, are free of DIF for age, disease duration and gender, display excellent overall reliability, and cover a range of functioning difficulties. This study illustrates that it is possible to measure functioning as a unidimensional construct based on selected ICF categories from the components body functions, as well as activities and participation of the Brief ICF-Core-Set for CWP in patients with FM.Keywords
This publication has 24 references indexed in Scilit:
- Identifying Fibromyalgia-Associated Symptoms and Conditions from a Clinical Perspective: A Step Toward Evaluating Healthcare Resource Utilization in FibromyalgiaPain Practice, 2010
- The International Classification of Functioning, Disability, and Health could be used to measure functioningJournal of Clinical Epidemiology, 2009
- Towards an ICF-based clinical measure of functioning in people with ankylosing spondylitis: A methodological explorationDisability and Rehabilitation, 2009
- Measuring health in patients with fibromyalgia: Content comparison of questionnaires based on the International Classification of Functioning, Disability and HealthArthritis Care & Research, 2008
- Fibromyalgia: Harmonizing Science with Clinical Practice ConsiderationsPain Practice, 2008
- Health economic consequences related to the diagnosis of fibromyalgia syndromeArthritis & Rheumatism, 2008
- Are the Contents of Treatment Outcomes in Fibromyalgia Trials Represented in the International Classification of Functioning, Disability, and Health?The Clinical Journal of Pain, 2007
- EULAR evidence-based recommendations for the management of fibromyalgia syndromeAnnals Of The Rheumatic Diseases, 2007
- ICF Core Sets for chronic widespread painJournal of Rehabilitation Medicine, 2004
- The american college of rheumatology 1990 criteria for the classification of fibromyalgiaArthritis & Rheumatism, 1990